Fig. 6.

Expression of UPR genes in developing pancreas and salivary glands. (A) Real-time RT-PCR quantification was performed for expression of select UPR genes in E14.5 and E18.5 pancreas, submandibular salivary gland, and liver samples. Chop, Gadd34, and Trb3 are genes in the proapoptotic pathway, whereas other genes primarily act in the adaptive pathways. Expression of the β-actin gene was used as reference. Data are mean ± SEM. Asterisks indicate statistically significant differences between WT and Sec23b^gt/gt samples (*P < 0.05 and **P < 0.01, Student t test). (B) Increased apoptosis in Sec23b^gt/gt tissues. Immunofluorescence staining for activated caspase-3 was performed on cryosections of E18.5 pancreas, fundus of stomach, and submandibular gland. Caspase-3–positive cells are visualized in green, and nuclei are stained blue with DAPI. (Scale bar: 100 μm.)